{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Geometries

# Geometries - solis(nrs545 H06 Geometries McCord(53130 This...

This preview shows pages 1–3. Sign up to view the full content.

solis (nrs545) – H06: Geometries – McCord – (53130) 1 This print-out should have 24 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 001 10.0 points Consider a 3-atom molecule A B A for which B has a total of only four valence elec- trons – enough to make two bonds. Predict the A-B-A bond angle. 1. 90 2. 109.5 3. 120 4. 180 correct 5. 60 Explanation: 002 10.0 points What is the shape of COCl 2 ? 1. trigonal planar correct 2. T-shaped 3. seesaw 4. tetrahedral 5. trigonal pyramidal Explanation: There are three regions of electron density (with no lone pairs) around the central atom: C Cl Cl O 003 10.0 points Which of the following has bond angles slightly LESS than 120 ? 1. I 3 2. O 3 correct 3. NO 3 4. SF 2 5. SO 3 Explanation: While SO 3 and O 3 have three regions of electron density around the central atom, only O 3 has a lone pair in one of these regions. The lone pair repels the other bonds more, which makes their angle slightly less than 120 . 004 (part 1 of 2) 10.0 points Draw the Lewis structure for NO 2 . How many single bonds, double bonds, triple bonds, and unshared pairs of electrons are on the central atom, in that order? 1. None of these 2. 3; 0; 0; 1 3. 2; 0; 0; 2 4. 1; 1; 0; 1 correct 5. 0; 1; 1; 0 6. 2; 1; 0; 0 7. 1; 0; 1; 0 8. 4; 0; 0; 0 9. 0; 2; 0; 0 10. 0; 0; 1; 1 Explanation: N has 5 valence electrons and O has 6 va- lence electron. The total number of valence electrons in the ion (plus one to account for the ion’s negative charge) is

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
solis (nrs545) – H06: Geometries – McCord – (53130) 2 5 + (2 × 6) + 1 = 18 The Lewis structure for NO 2 can be found by connecting the oxygen atoms to nitrogen and placing eight electrons around each atom: bracketleftbigg O N O bracketrightbigg and the central atom has one single bond, one double bond, and one unshared pair of electrons. 005 (part 2 of 2) 10.0 points Determine the molecular geometry of the ion NO 2 . 1. linear 2. octahedral 3. trigonal-bipyramidal 4. tetrahedral 5. bent or angular correct 6. trigonal-planar 7. trigonal-pyramidal 8. None of these Explanation: The central atom N has 2 bonding regions and 1 lone pair of electrons. The three areas of high electron density make the electronic geometry trigonal planar and the molecular
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 6

Geometries - solis(nrs545 H06 Geometries McCord(53130 This...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online